Antidepressant treatments may include therapies that target monoaminergic (MA) systems. Antidepressant treatments that target monoaminergic (MA) systems may require 4-6 weeks of administration to achieve effects, may include unpleasant side effects, may possess modest efficacy rates, and may display significant relapse rates. N-Methyl-D-aspartate (NMDA) receptor antagonists may be used as anesthetics and hallucinogenic recreational drugs. Ketamine, diethyl ether, dizocilpine, memantine, phencyclidine, nitrous oxide, and dextromethorphan may be MNDA receptor antagonists.